The subject matter disclosed herein relates to robotic devices that move across a vertical surface. There are three major challenges in using vacuum to attach and move across a wall. The first challenge is maintaining mobility while at the same time sticking strongly to the wall. This first challenge is significant as these properties are contradictory. The second challenge is maintaining a seal while moving across the wall. This is difficult as there are many types of surfaces such as flat surfaces or faces with curvatures as well as surface features, such as seams or ridges, which may make it difficult to maintain a vacuum seal. The third challenge is avoiding debris that can damage the impeller or vacuum motors. It is very common for concrete structures to have debris that are likely to damage the device. An improved device is therefore desirable.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.